[Metabolomic profiling reveals blood-tonifying effect of Rehmanniae Radix Praeparata based on theory of activating spleen and generating blood].

Based on the theory of activating spleen and generating blood, this study explored the effect of Rehmanniae Radix Prae-parata on the spleen metabolome of the rat model with blood deficiency syndrome.The rat model of blood deficiency syndrome was established by combining with cyclophosphamide(CTX) and N-acetyl-phenylhydrazine(APH), and the metabolomes of the spleen samples were analyzed with ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS).Principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) were carried out for the metabolite profiles of spleen samples.The MEV heatmap and metabolic network were established based on the potential biomarkers.Finally, the blood routine indexes were combined with the metabolomic profile to reveal the mechanism of Rehmanniae Radix Praeparata in activating spleen and generating blood.The treatment with CTX and APH decreased the blood routine indexes such as white blood cell count(WBC), red blood cell count(RBC), platelet(PLT), and hematocrit(HCT), indicating that the rat model of blood deficiency syndrome was successfully established.The administration of Rehmanniae Radix Praeparata significantly improved the blood routine indexes, which suggested that Rehmanniae Radix Praeparata played a role in replenishing blood.In addition, the metabolomics analysis identified 41 potential biomarkers.The PCA and MEV heatmap also showed significant improvement effect of Rehmanniae Radix Praeparata on the spleen metabolic profile.These potential biomarkers were mainly involved in tricarboxylic acid cycle, niacin and nicotinamide metabolism, phenylalanine metabolism, tyrosine metabolism, taurine and hypotaurine metabolism, and sphingolipid metabolism.Therefore, we hypothesize that Rehmanniae Radix Praeparata may regulate energy metabolism, peripheral blood production, and oxidative injury of hemocytes to tonify blood.